It is well known to form paperboard containers or boxes that use extra wall layers to increase wall thickness at the corners of the container to improve stacking strength. Such containers are typically used with products that are unusually heavy, e.g., frozen meat, paper files, books, canned goods, etc.
Examples of such a container are shown in U.S. Pat. No. 5,000,377, U.S. Pat. No. 6,402,020, U.S. Pat. No. 6,575,356, and U.S. Pat. No. 6,595,411, the disclosure of which is incorporated in full herein by reference. These prior containers use doubled-over reinforcing panel sub-assemblies at its interior corners and optionally glue flaps about its exterior upper surface. Many of these containers are typically formed by machine. However, this can be a problem for small business that cannot afford the huge investment required to install tray formers and case sealers. To date, small manufacturers have had to settle for much more expensive and less efficient box styles than their large competitors. These expensive and less efficient box styles include “swing under” styles, double wall RSC's (regular slotted containers), and various combinations of hand-erected trays and HSC's (half slotted containers), all of which require much more paperboard for a given endurance level.
Therefore, it is desirable to provide a corrugated paperboard container having locking features to help maintain the container from opening when outward pressure was applied at the side walls or when the lid of the container was folded away from the container as the container is filled.